Impatiens Necrotic Spot Virus (INSV) was confirmed in the UMass Extension Plant Diagnostic Lab this week on pepper seedlings grown in a greenhouse. INSV has host range that spans 300 species including vegetables, ornamentals, and weeds. It is not seed-borne, but it is spread through vegetative propagation of infected plant material and by several species of thrips including western flower thrips. Symptoms of INSV on pepper include leaf distortion and tan or brown lesions that may or may not be circular. Wilting and necrosis of meristems may also occur.
Management starts with discarding infected plants. Monitor and manage thrips populations in the greenhouse. Carefully inspect all incoming plant material for disease symptoms and thrips. Vegetable transplants and susceptible ornamentals should be grown in separate greenhouses. Keep the greenhouse free of weeds, as many species can harbor both INSV and the thrips that transmit it.